Grade III coronary heart disease is already a serious heart disease, patients should pay attention to it and actively cooperate with doctors for treatment. Coronary heart disease belongs to a common heart disease, according to the Canadian Cardiovascular Society’s CCS grading and classification method can be divided into four levels. Grade I: Patients suffer from heart disease, but patients will not have obvious limitations in their activities, no obvious palpitations, angina pectoris. Grade 2: The patient will have mild cardiac symptoms after activity, which disappear after rest. Grade III: The patient will have obvious cardiac symptoms with light activity. Grade IV: Patients will experience angina with any physical activity. Grade III coronary heart disease is already a serious heart disease, the patient should go to the regular hospital in time to consult the doctor, and actively carry out treatment, do not advocate self-assessment of the degree of the disease, to avoid misunderstanding the condition.